linkedList drop

  final def drop(n: Int): LinkedList[A] = {
    val len = (this.length - n)

    @tailrec def inner(remaining: LinkedList[A]): LinkedList[A] =
      remaining match {
        case Nil() => Nil()
        case Cons(h, t) => if (t.length > len) inner(t) else t
    }
    if (n > this.length) Nil()

    else inner(this)
  }